The original grant was directed to establish whether in man aldosterone is bound to specific or non-specific binding proteins in normal and hypertensive blood. Related to the form of aldosterone in the circulation was an in vivo study of aldosterone metabolic clearance and plasma and whole blood in both normal and hypertensive subjects. The grant renewal will build on conclusions reached in the previous period as well as current literature to explore additional control mechanisms and kinetics of aldosterone and DOC. We shall further define a new syndrome discovered in critically ill patients of high renin and hypoaldosterone suggesting a block in mineralocorticoid production by the adrenal. Preliminary data suggests this is potentially reversible. In a second project we shall determine whether dopamine agonists can alter secondary hyperaldosteronism in liver disease. Thirdly, DOC binding and kinetics will be related to aldosterone in hypertensive patients. We shall also explore whether aldosterone binding to albumin, transcortin, and red cells alter uptake by target tissues.